Graph the linear function.

satela [25.4K]

It would be the last one because uvw is congruent to xvy

hope it helps :)

4 0

3 years ago

A researcher wishes to estimate the percentage of adults who support abolishing the penny. What size sample should be obtained i

Scorpion4ik [409]

Answer:

a) We need a sample size of at least 3109.

b) We need a sample size of at least 4145.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

The margin of error is:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

99% confidence level

So $\alpha = 0.01$ , z is the value of Z that has a pvalue of $1 - \frac{0.01}{2} = 0.995$ , so $Z = 2.575$ .

(a) he uses a previous estimate of 25%?

we need a sample of size at least n.

n is found when $M = 0.02, \pi = 0.25$ . So

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.02 = 2.575\sqrt{\frac{0.25*0.75}{n}}$

$0.02\sqrt{n} = 2.575\sqrt{0.25*0.75}$

$\sqrt{n} = \frac{2.575\sqrt{0.25*0.75}}{0.02}$

$(\sqrt{n})^{2} = (\frac{2.575\sqrt{0.25*0.75}}{0.02})^{2}$

$n = 3108.1$

We need a sample size of at least 3109.

(b) he does not use any prior estimates?

When we do not use any prior estimate, we use $\pi = 0.5$

So

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.02 = 2.575\sqrt{\frac{0.5*0.5}{n}}$

$0.02\sqrt{n} = 2.575\sqrt{0.5*0.5}$

$\sqrt{n} = \frac{2.575\sqrt{0.5*0.5}}{0.02}$

$(\sqrt{n})^{2} = (\frac{2.575\sqrt{0.5*0.5}}{0.02})^{2}$

$n = 4144.1$

Rounding up

We need a sample size of at least 4145.

8 0

3 years ago

There are some Chicken and rabbits in a cage. There are 20 heads and 62 feet in total, the question is: how many chicken and rab

horsena [70]

Answer:There are 72 heads (chicken and rabbit) and 200 legs. How many chickens and rabbits are present totally?

Step-by-step explanation

There are 72 heads (chicken and rabbit) and 200 legs. How many chickens and rabbits are present totally?

Legs of a chicken = 2

Legs of a rabbit = 4

Total heads = 72

Total legs= 200

Let's assume that each of them has minimum 2 legs.

So 72*2 = 144 legs

Remaining legs: 200-144= 56

These remaining legs belong to rabbit because rabbit has 4 legs each.

2*Rabbits= 56

Rabbits= 56/2 = 28

Out of 72, 28 are rabbits. So there are 72-28= 44 chicken.

5 0

2 years ago

A Jewelry Company sells a bracelet and gives customers the option to purchase charms to add to the bracelet. The expression 60+2

vlabodo [156]

Answer: the price per charm

Step-by-step explanation:

not really sure but i think 60 is the price of the beacelet and since x is the charms 25 must be the price per charm because 25 is multiplyed with x.

does that make sense?

7 0

3 years ago

The value of a company’s stock is represented by the expression x2 – 2y and the company’s purchases are modeled by 2x + 5y. The

musickatia [10]

The answer is the first two inequalities ........

5 0

2 years ago